Problem: Rewrite ${\dfrac{7^{-6}}{7^{-3}}}$ in the form ${7^n}$.
${ \dfrac{7^{-6}}{7^{-3}} = 7^{-6-(-3)}} $ ${ \hphantom{\dfrac{7^{-6}}{7^{-3}}} = 7^{-3}} $